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81.
Patricia Quinlin Herman J. Weiser Jr. 《Journal of the American Oil Chemists' Society》1958,35(7):325-327
Summary Monoglyceride concentrates are quantitatively separated into mono-, di-, and triglyceride components on silica gel columns
by an adsorption chromatographic technique. The separated glycerides are determined gravimetrically. The adsorption on silica
gel is dependent on the number of hydroxyl groups in the molecule, and the influence of unsaturation and chain length is minimized.
Combinations of benzene and ethyl ether are used for elution, thus preventing isomerization, which frequently results when
polar solvents such as alcohols are used.
The procedure for the chromatographic separation is simple and straightforward. The equipment used is easily obtainable. The
silica gel adsorbent requires only adjustment of its water content before use.
Mixtures of both saturated and unsaturated glycerides and those having different fatty acid chain length have been separated.
Known mixtures have also been analyzed. For a known mixture containing 15% tripalmitin, 45% distearin, and 38% monopalmitin
the average deviations from the calculated values were 0.4%, 0.2%, and 0.6%, respectively 相似文献
82.
Roshan Lalintha Peiris Mili John Tharakan Owen Noel Newton Fernando Adrian David Cheok 《Multimedia Tools and Applications》2013,66(1):81-94
This paper presents, AmbiKraf, a non-emissive fabric display that subtly animates patterns on common fabrics. We use thermochromic inks and peltier semiconductor elements to achieve this technology. With this technology we have produced numerous prototypes from animated wall paintings to pixilated fabric displays. The ability of this technology to subtly and ubiquitously change the color of the fabric itself has made us able to merge different fields and technologies with AmbiKraf. In addition, with an animated room divider screen, Ambikraf merged its technology with Japanese Byobu art to tighten the gap between traditional arts and contemporary technologies. Through this AmbiKraf Byobu art installation and other installations, we discuss the impact of this technology as a ubiquitous fabric display. With focus to improvements of some limitations of the existing system, we present our future vision that enables us to merge this technology into more applications fields thus making this technology a platform for ubiquitous interactions on our daily peripherals. 相似文献
83.
Nicole Basaraba Owen Conlan Jennifer Edmond Peter Arnds 《New Review of Hypermedia and Multimedia》2013,19(1-2):1-30
ABSTRACTGalleries, libraries, archives and museums (GLAMs) are increasingly using digital technologies for storytelling and creating mobile applications (apps) for cultural heritage content, but how apps are used in practice to communicate information to users has not been widely studied. A team of people from a heritage organisation, a university, and mobile app development group plan to create a bespoke heritage trail app for Ireland, but to date design conventions/recommendations for this genre are lacking. This article applies a systematic approach to digital narrative content analysis to better understand how apps are being used specifically for heritage trails with the aim of identifying what the common features are, which modalities and narrative techniques are used. The selected corpus included 55 apps downloaded from the Google Play Store. The results of this content analysis—based on the App Walkthrough Method (Light, B., Burgess, J., & Duguay, S. (2018). The walkthrough method: An approach to the study of apps. New Media & Society, 20(3), 881–900)—show that there is a gap between academic research themes/trends and how digital narrative is actually being communicated in the current market, and it aims to inform the future development of heritage trail apps by including a list of design and content features common to this genre. 相似文献
84.
Abstract Representation of ideas so that others may understand them is vital, and particularly so in the early stages of the design process; designers use many different techniques to make these representations. Recent work at the Visualisation and Information Design Centre (VIDe) at the Coventry School of Art and Design has concentrated on supporting styling design. The previously‐developed technique of mapping 2D images over 3D computer models of vehicles has been extended: now, 2D facial photographs are mapped onto generic 3D head‐models to enhance a new technique for spectacle design. A summary of work in progress for computer assisted spectacle design, and for rapid car styling, is described here, along with details for improvements in sketch modelling, including texture mapping. Photographs and reference CAD models are used in an attempt to verify the basic process; also ‘depth mapping’, ‘lines in space’ and other rapid modelling methods are discussed. Three different strategies for rapid computer modelling of cars are described and evaluated to ascertain if they may replace or enhance standard methods. 相似文献
85.
Dynamic memory allocation has been used for decades. However, it has seldom been used in real-time systems since the worst
case of spatial and temporal requirements for allocation and deallocation operations is either unbounded or bounded but with
a very large bound.
In this paper, a new allocator called TLSF (Two Level Segregated Fit) is presented. TLSF is designed and implemented to accommodate
real-time constraints. The proposed allocator exhibits time-bounded behaviour, O(1), and maintains a very good execution time. This paper describes in detail the data structures and functions provided by
TLSF. We also compare TLSF with a representative set of allocators regarding their temporal cost and fragmentation.
Although the paper is mainly focused on timing analysis, a brief study and comparative analysis of fragmentation incurred
by the allocators has been also included in order to provide a global view of the behaviour of the allocators.
The temporal and spatial results showed that TLSF is also a fast allocator and produces a fragmentation close to that caused
by the best existing allocators.
相似文献
Alfons Crespo (Corresponding author)Email: |
86.
This paper is concerned with the derivation of infinite schedules for timed automata that are in some sense optimal. To cover
a wide class of optimality criteria we start out by introducing an extension of the (priced) timed automata model that includes
both costs and rewards as separate modelling features. A precise definition is then given of what constitutes optimal infinite
behaviours for this class of models. We subsequently show that the derivation of optimal non-terminating schedules for such
double-priced timed automata is computable. This is done by a reduction of the problem to the determination of optimal mean-cycles
in finite graphs with weighted edges. This reduction is obtained by introducing the so-called corner-point abstraction, a
powerful abstraction technique of which we show that it preserves optimal schedules.
This work has been mostly done while visiting CISS at Aalborg University in Denmark and has been supported by CISS and by
ACI Cortos, a program of the French Ministry of Research. 相似文献
87.
Initial algebra semantics is one of the cornerstones of the theory of modern functional programming languages. For each inductive
data type, it provides a Church encoding for that type, a build combinator which constructs data of that type, a fold combinator which encapsulates structured recursion over data of that type, and a fold/build rule which optimises modular programs by eliminating from them data constructed using the buildcombinator, and immediately consumed using the foldcombinator, for that type. It has long been thought that initial algebra semantics is not expressive enough to provide a similar
foundation for programming with nested types in Haskell. Specifically, the standard folds derived from initial algebra semantics have been considered too weak to capture commonly occurring patterns of recursion
over data of nested types in Haskell, and no build combinators or fold/build rules have until now been defined for nested types. This paper shows that standard folds are, in fact, sufficiently expressive for programming with nested types in Haskell. It also defines buildcombinators and fold/build fusion rules for nested types. It thus shows how initial algebra semantics provides a principled, expressive, and elegant
foundation for programming with nested types in Haskell. 相似文献
88.
The network function virtualization (NFV) paradigm replaces hardware-dependent network functions by virtual network functions (VNFs) that can be deployed in commodity hardware, including legacy servers. Consequently, the use of NFV is expected to reduce operating and capital expenses, as well as improve service deployment operation and management flexibility. For many use cases, the VNFs must be visited and invoked following a specific order of execution in order to compose a complete network service, named service function chain (SFC). Nonetheless, despite the benefits from NFV and SFC virtualization technologies, their introduction must not harm network performance and service availability. On the one hand, redundancy is seen by network service planners as a mechanism well established to combat availability issues. At same time, there is a goal to optimize resource utilization in order to reduce operational expenditure. In this article, we share our experience in the design use of a framework, named SPIDER, focused on SFC placement that considers the network infrastructure condition and the required SFC availability to define the placement strategy. The SPIDER monitors the status of infrastructure nodes and links and defines which servers the VNFs should be placed on and the number of redundant replicas needed. We present a proof-of-concept of SPIDER using Kubernetes to launch the VNFs as containers. We also use Kubernetes to forward the traffic between the VNFs, composing the service chain. We perform experiments to evaluate the runtime of SPIDER and the SFC delay under different network conditions. 相似文献
89.
Farrugia Russell Portelli Barnaby Grech Ivan Camilleri Duncan Casha Owen Micallef Joseph Gatt Edward 《Microsystem Technologies》2022,28(6):1451-1465
Microsystem Technologies - The maximum scan angle amplitude of resonating micro-mirrors, intended for micro-projection display applications is limited by air damping. Three-dimensional transient... 相似文献
90.
Mery Patricia Tamayo 《Industry and innovation》2017,24(2):143-164
This paper analyses the determinants of R&D offshoring of Spanish firms using information from the Panel of Technological Innovation. We find that being an exporter, international technological cooperation, continuous R&D engagement, applying for patents, being a foreign subsidiary, and firm size are factors that positively affect the decision to offshore R&D. In addition, we find that a lack of financing is an obstacle relatively more important for independent firms than for firms that belong to business groups. For these latter, we also obtain that the factors that influence the decision to offshore R&D differ depending on whether the firm purchases the R&D services within the group or through the market: a higher degree of importance assigned to internal sources of information for innovation as compared to market sources increases (decreases) the probability of R&D offshoring only through the group (market). 相似文献